These accrete—meaning merge and combine—into an accretion disk that surrounds the SMBH. (Stars, in turn, can have their own accretion disks, so it’s accretion all the way down.) For certain ...

Cataclysmic variables are binary star systems in which a compact stellar remnant, typically a white dwarf star, is stripping mass from a lower main‐sequence companion star by way of an accretion disk.